Feature:1. Efficient Alarm: Even a slight vibration can trigger the alarm, more sensitive, can be a good protection of your property and items.2. Wide Application: Wired rolling shutter door magnetic alarm can be used for different types of doors such as rolling gates and rolling shutter doors.3. Easy Installation: No need for complex circuit connection, just simple installation can be enabled, providing you with convenience.4. Strong Adsorption Force: The magnet end uses strong magnetic glue, and the induction is more sensitive.5. Anti Theft Function: Effectively prevent theft and intrusion, to protect the security of the home and the store, is a very practical tool.Specification:Item Type: Door Magnetic Contacts Switch SensorWeight: 168g/5.9ozSensing Distance :50-70mm/2-2.8inMaterial: Aluminum alloy silver gray platingSuitable for Working Voltage: 12VApplicable to Working Current: 500maContact Mode: (NC\NO) Normally closedInstallation Mode: buried, surface installationScope: Applicable to all kinds of rolling shutter doors.Package List:1 x Magnetic Contact Switches 4 x Screws 1 x Accessory